package cn.xiaoliu.basic.interceptor;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.concurrent.TimeUnit;

@Component
public class LoginInterceptor implements HandlerInterceptor {
    @Autowired
    private RedisTemplate redisTemplate;
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws IOException {
        //1.检查token是否有值
        String token = request.getHeader("token");
        if (!StringUtils.isEmpty(token)){
            //如果有值，就从redis中拿，并且设置刷新时间
            Object loginTmp = redisTemplate.opsForValue().get(token);
            //如果查到了登录用户，就放行并且刷新过期时间
            if (loginTmp != null){
                redisTemplate.opsForValue().set(token,loginTmp ,30, TimeUnit.MINUTES );

                //@TODO 可以自己加权限校验  即使登录了，也要看你有没有访问资源的权限
                return true;//放行
            }

        }
        //如果没有值，就报错，不放行
        response.setContentType("application/json;charset=utf-8");
        response.setCharacterEncoding("UTF-8");
        PrintWriter writer = response.getWriter();
        writer.write("{\"success\":false,\"message\":\"noLogin\"}");
        writer.flush();
        writer.close();
        return false; //阻止放行
    }
}
